Venus Express is on its way

Europe's Venus Express mission successfully blasted off from the Baikonur Cosmodrome in Kazakhstan in the small hours of this morning. Mission controllers received a signal from the craft some 90 minutes after launch, confirming that all was well.

It will spend the next five months en route to our sister planet where it will study the atmosphere and planetary surface for clues about Venus' past. Scientists hope that some of the data might illuminate the mechanics of climate change more fully, and help us to understand weather systems on our own planet.

"With Venus Express, we fully intend to demonstrate yet again that studying the planets is of vital importance for life here on Earth," said Jean Jacques Dordain, ESA's director general.

"To understand climate change on Earth and all the contributing factors, we cannot make do with solely observing our own planet. We need to decipher the mechanics of the planetary atmosphere in general terms."

The next big challenge for Venus Express will come just as it arrives at the planet, when the engines will need to wake up to complete a long, sustained braking burn to slot the craft into its orbit.

Although the Venus Express craft is based on the same design as the Mars Express mission, and carries many similar experiments, the Venusian Gravity is much greater than that of Mars, meaning the braking will have to be more severe.

When Venus Express arrives at its destination in April 2006 it will drop into an elliptical polar orbit. At perigee (the closest approach to the planet) it will orbit a mere 250km above the planet's surface, while its apogee (furthest away) will take it to a distance of some 66,000km.

Its job will be to peer through the dense cloudy atmosphere and gather data that will help scientists unravel some of the unusual phenomena observed in the Venusian clouds. It will also study the surface of the planet, looking for signs of geological activity. ®